Photoelectric inspection device



-4 2, 1941- F. H. GULLIKSEN 2,265,037

I PHOTOELECTRIC INSPECTION DEVICE Filed Sept. 7, 1939 INVENTOR WITNESSES:

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' ATTORNEY Patented Dec. 2, 1 941 J Finn H. Gulliksen, Pittsburgh, Pa, assignoito Westinghouse Electric & Manufacturing Company, East Pittsburgh,

Pennsylvania Pa., a corporation of Application September'7, 1939, Serial No. 293,733

' (c1. ss-14) 15 Claims.

My invention relates to apparatus for automatically detecting the presence of foreign bodies on the bottom of a transparent container, such as, for'example, a glass bottle.

The most common way of inspecting bottles at present is visually as they leave the bottle washing machine at a rate of up to 120 bottles per minute. Even with the most careful inspection, it isfreque'ntly found that dirty bottles or bottles'with glass splinters are not detected by the inspectors, with the result of loss of customers goodwill, or of laying the basis for a damage suit. Heretofore, one of the main difliculties encountered in attempts to scan the bottom of bottles and other vessels was the presence of trade names in the form of raised impressions projecting from the bottom of the glass bottle. 7

Scanning devices have been unsuccessful due to the inability to distinguish between such raised impressions and the presence of glass splinters or of dirt on the bottom of the bottles.

- An object of my invention is to provide a spe- I cial type of diffuser immediately beneath the bottom of the bottle between the light source and a light sensitive device in order to overcome the effects of raised impressions upon the successful operation of a scamiing device for transparent vessels such as glass bottles.

Another object of my invention is to provide a light sensitive scanning device for detecting the presence of foreign :bodies on the bottom of transparent vessels which comprises a simple, inexpensive, but reliable, scanner' which produces alight beam having a spiral motion during the scanning process.

Another object of my invention is to provide a novel positioning of a light source with respect to a light sensitive device in scanning the bottom of a transparent vessel wherein the light source is placed beneath the bottom of the vessel and the light sensitive device is placed above the opening of such vessel.

Other objects and advantages willbecome more apparent from a study of the following specification when considered in conjunction with the accompanying drawing, in which:

Figure 1 is a schematicshowing of an apparatus for detecting the presence of foreign bodies gear 8. .One lamp terminal is preferably connected to tube 6 and the other lamp terminal is connected to a lead inside tube 6. On top of the container 3 is arranged a disc shaving a rectangular slot Ill as shown in Fig. 2 This disc is equipped with two rollers H and I2 which support a flexible opaque ribbon l3 which fits snugly in the rectangular slot [0. This ribbon has a circular hole, and covering this hole is a lens !4.

From Fig. 1 it will be seenthat the ribbon I3 is supported on one side by spring l5 and on the other side by a string of wire l6connected to the crank of gear assembly l'l. Gear assembly I! rotates with container 3 and is driven by the stationary gear 8.

When the motor drive'shaft 4 rotates, lens M will have a primary'circular movement relative to the motor axis,. and a secondary lateral or radial movement as caused by the action of the crank on ribbon l3. The resultant movement of lens 14 is therefore in the form of, a spiral, so that the beam of light projected scans the entire bottom of the bottle.

Above the bottle opposite its opening aphototube I8 is arranged as shown in Fig. 1. This phototube is connected to an impulse type ampliiier l9 of any suitable conventional type which operates a bell 20 if a sudden variation in light illumination onthe phototube occurs as a result of dirt spots or glass splinters in the bottle.

The success of this inspection device depends for all types of bottles, in large measure on the Nearlyall bottles used in trade have trade marks or lettering projecting from the bottom, and the thickness of the glass bottom is therefore not uniform. This varying thickness causes a lens action, so that if plate 2! were not used, the signal hell 2!] would operate on a perfectly clean bottle.

-I have found that this condition can be. eliminated by inserting atranslucent plate 2| between the lens l4 and the bottle i. This plate ZI should be made of a material which diffuses the light beam during its entire passage through the plate.

White urea, 3 5 inch thick, is especially suitable.

Milk glasscan also be used,'but frosted glass which diffuses on the surface only is not suitable. In order to eliminate the effect of the lens action I of the raised sections of the glass bottle, it was found that the upper part of plate 2! should not Q be more than 3 5 inch distant from the lower end hollow tube 6 which is stationary and which supports a stationary lamp I and a stationary of the bottle I.

It is thus seen that by interpositioning the translucent diffuser in the position described above, a successfully operative device for detecting the presence of foreign bodies on the bottom of transparent vessels is obtained. It is obvious, of course, that while a spiral scanning motion has been described, other types of scanning motions which may not have all the advantages of a spiral motion may be substituted and may be operative due to the action of the diffusing plate.

I am, of course, aware that others, particularly after having had the benefit of the teachings of my invention may devise other apparatus embodying my invention, and I, therefore, do not wish to be limited to the specific showing made in the drawing and the descriptive showing hereinbefore made, but wish to be limited only by the scope of the appended claims and such prior art that may be pertinent.

I claim as my invention:

1. Apparatus for detecting the presence of foreign bodies on the bottom of a transparent vessel comprising in combination. a support for said 'vessel, a light source, means for moving a light beam emanating from said light source in a spiral path on the bottom of said vessel when said vessel is in position on said support, a light sensitive device on the opposite side of said vessel bottom for receiving said light beam and means operable under the control of said light sensitive device to givea signal or indicationv when the light falling on the light sensitive device is suddenly reduced below a predetermined value, thereby indicating the presence of foreign bodies.

2. Apparatus for detecting the presence of foreign bodies on the bottom'of a transparent vessel comprising, in combination, a support for said vessel, alight source situated beneath the bottom of said vessel, means for moving a light beam emanating from said light source in a spiral path on the bottom of said vessel when said vessel is in position on said support, a light sensitive device situated above the top of said vessel opposite the opening of said vessel for receiving said light beam, and means operable under the control of said light sensitive .device to give a signal or indication when the light falling on the light sensitive device is suddenly reduced belowa predetermined value, thereby indicating the presence of foreign bodies.

3. Apparatus for detecting the presence of for- I eign bodies on the bottom of a transparent vessel comprising, in combination, a support for said.

vessel, a light source situated beneath the bottom of said vessel, means for moving a light beam emanating from said light 'source in a spiral path on the bottom of said vessel when said vessel is in position on said support, allight sensitive device situated above the top of said vessel opposite the opening of said vessel for receiving said light beam, a diffusing, translucent plate located between the light source and the bottom of said vessel and closely spaced from the latter, and means operable under thecontrol of saidlight sensitive device to give a signal or indication when the light falling on the light sensitive device is suddenly reduced below a predetermined value. thereby indicating the presence of foreign bodies. V V

4. Apparatus for detecting the presence of foreign bodies on the bottom of a transparent vessel comprising, in combination, a support for said vessel, alight source situated beneath the bottom of said vessel, means for moving a light beam emanating from said light source in a spiral path on the bottom of saidvessel when said vesselis in position on said support, a light sensitive device situated above the top of said vessel opposite the opening of said vessel for receiving said light beam, a diffusing translucent plate located beneath and immediately adjacent the bottom of said vessel for eliminating the client of any printed impressions which are integral with the bottom of said vessel, and means operable under the control-of said light sensitive device to give a signal or indication when the light falling on the light sensitive device is suddenly reduced below a predetermined value, thereby indicating the presence of foreign bodies.

5. Apparatus for detecting the presence of foreign bodies on the bottom of a transparent vessel comprising, in combination, a support for saidvessel, a light source, means for scanning the bottom of said vessel by a beam emanating from saidlight source, a light sensitive device on the opposite side of said vessel bottom for receiving said light beam, and an internally difiusing, translucent plate located in the path of said light beam and immediately adjacent the bottom of the vessel.

6. Apparatus for detecting the presence of foreign bodies on the bottom of a transparent vessel comprising, in combination, a support for said vessel, a light source situated beneath the bottom of said vessel, means for scanning the bottom of said vessel by moving a light beam emanating from said light source in a spiral path, a light sensitive device situated above the top of said vessel opposite the opening of said vessel for receiving said light beam, and means operable under the control of said light sensitive device to give a signal or indication when the light falling on the light sensitive device is sud- "denly reduced below a predetermined value,

thereby indicating the presence of foreign bodies.

7. Apparatus for detecting the presence of foreign bodies on the bottom of a transparent vessel comprising, in combination, a support for said vessel, a light source situated beneath the bottom of said vessel, means for scanning the denly reduced below a predetermined value,

thereby indicating the presence of foreign bodies.

8. Apparatus for detecting the presence. of foreign bodies on the bottom of a transparent vessel comprising, in combination, a support for said vessel, a light source, means for scanning the bottom of said vessel by a beam emanating from said light source, a light sensitive device on the opposite side of said vessel bottom for receiving said light beam, and a diffusing, translucent plate of white urea located in the path of said light beam immediately adjacent the bottom of said vessel.

9. Apparatus for detecting the presence of foreign bodies on the bottom of a transparent.

vessel comprising, in combination, a support for said vessel, a light source, means for scanning the bottom of said vessel by a beam emanating from said light source, a light sensitive device on the opposite side of said' vessel bottom for receiving said light beam, and a diffusing, translucent plate of milky glass located in the path of said light beam immediately adjacent the bottom of said vessel.

10. Apparatus for detecting the presence of tor said container situated above the top of said vessel opposite the opening of said vessel for receiving said light beam, a difiusing translucent plate of white urea located beneath and immediately adjacent the bottom of said vessel for eliminating the efiect of any printed impressions which are integral with the bottom of said vessel, and means operable under the control of said light sensitive device to give a signal or indication when the light falling on the light sensitive device is suddenly reduced below a predetermined value, thereby indicating the presence of foreign bodies.

11. Apparatus for detecting the presence of foreign bodies on the bottom of a transparent vessel comprising, in combination, a support for said vessel, a light source situated beneath the bottom of said vessel, means for scanning the bottom of said vessel by a light beam emanating from said light source, a light sensitive device situated above the top of said vessel opposite the opening of said vesselfor receiving said light beam, a difiusing translucent plate of milky glass located beneath and immediately adjacent the bottom of said vessel for eliminating the efiectof any printed impressions which are integral with the bottom of said vessel, and means operable under the control of said light sensitive device to 'give a signal or indication when the light falling on the light sensitive device is suddenly reduced below a predetermined value, thereby indicating 12. Apparatus for detecting the presence of foreign bodies on the bottom of a transparent vessel comprising, in combination, a support for said vessel, a light source, means for moving a light beam emanating from said light source in a spiral path on the bottom of said vessel, comprising a rotatable container, a motor for rotating said container, an opaque screen forming a cover for said container and having a hole therein, a lens snugly fltt' g in said hole, said light source being stationary and located within .said container, gearing .means for translating rotary motion of said container into radial motion of said cover thereby producing a light beam emanating from said lens having a spiral motion, a light sensitive device at the top of the vessel for receiving said light beam and means operable under the control of said light sensitive device to give a signal or indication when the light falling on the light sensitive device is suddenly reduced below a predetermined value, thereby indicating the presence of foreign bodies.

13. Apparatus for detecting the presence of foreign bodies on the bottom of a transparent vessel comprising, in combinatio a support for said vessel, a light source situated beneath the bottom of saidvessel, means for moving a. light beam emanating from said light source in a the presence of foreign bodies tainer, gearing means for translating rotary motion of said container into radial motion of said cover thereby producing a light beam emanating from said lens having a spiral motion, a light sensitive device situated above the top of said vessel opposite the opening of said vessel for receiving said light beam, and means operable under the control of said light sensitive device to give a signal or indication when the light fallingon the light sensitive device is suddenly reduced below a predetermined value, thereby indicating the presence of foreign bodies.

14. Apparatus for detecting the presence of foreign bodies on the bottom of a transparent vessel comprising, in combination, a support for said vessel, a light source -s'tuated beneath the bottom of said vessel, means for moving a light beam emanating from said light source in a spiral path on the prising arotatable container, a motor for rotating said container, a flexible opaque screen guided on rollers and forming a cover for said container and having a hole which contains a lens therein, said light source having 'a stationary mounting within and independent of said container, gearing means for translating rotary motion of said container into radial motion of said cover guided by said rollers thereby producing a light beam emanating from said hole and onto the bottom of said-vessel having a spiral scanning motion, a light sensitive device situated above the top of said vessel opposite the opening of said vessel,for receiving said light beam, and means operable under the control of said light sensitive device to give a signal or indication when the light falling on the light sensitive device is suddenly reduced below a predetermined value, thereby indicating the presence of foreign bodies.

15. Apparatus for detecting the presence of foreign bodies on the bottom of a transparent vessel comprising, in combination, a support for said vessel, a light source situated beneath the bottom of said vessel, means for moving a light beam emanating from said light source in a spiral path on the bottom of said vessel, comprising a rotatable container, a motor having a sleeve type drive shaft rigidly secured to said container for rotating said container, a flexible opaque screen guided on rollers and forming a cover for said container and having a hole which contains a lens therein, a stationary tube contained within said drive shaft and concentrically mounted with respect thereto, said light source rigidly connected to said imparting radial motion to said cover as it is being rotated together with said container thereemanating from said lens andonto the spiral scanning motion, a light sensitive device I situated above the top of said vessel opposite the said light sensitive device to spiral path on the bottom of said vessel, compnsing a rotatable container, a motor for rotating said container, an opaque screen forming a cover and having a hole therein, a lens snugly fitting in said hole, said light source being stationary and located-within said conopening of said vessel for receiving said light beam,-and means operable under the control of dication when the light falling on the light sensitive device is suddenly reduced below a predetermined value, thereby indicating the presence of foreign bodies,

, FINN H. GULJIKSEN.

bottom of said vessel, comstationary tube for give a signal or in- 

